Comprehensive Guide for Oracle Application Developers

JPA注解参考_Oracle.chm通过它可以全面的掌握JPA编程。

Oracle索引是数据库性能优化的重要手段。本书是关于索引类型和索引设计的经典参考，详细讲述了各种索引的应用和实现方式，是每位开发者必备的资源。

The professional's one-stop guide to this open-source, Java-based big data framework, Professional Hadoop is the complete reference and resource for experienced developers aiming to implement Apache Hadoop in real-world settings. Written by a team of certified Hadoop developers, committers, and Summit speakers, this book details every key aspect of Hadoop technology to enable optimal processing of large data sets. Tailored specifically for the professional developer, this book bypasses the basics of database development to dive directly into the framework's processes and capabilities. Each key Hadoop component is discussed individually, culminating in a sample application that integrates all components to illustrate the cooperative dynamics that make Hadoop a significant solution in the big data landscape. Coverage spans storage, security, computing, and user experience, with expert guidance on integrating additional software and tools.

PRIMARY KEY约束为表创建一个主键。每个表只能创建一个主键。PRIMARY KEY约束是表中的对行唯一标识的一个列或者列组合，该约束强制列或列组合的唯一性，并且确保作为主键一部分的列不能包含空值。既可以定义在表级也可以定义在列级： CREATE TABLE departments ( department_id NUMBER(4), department_name VARCHAR2(30) CONSTRAINT dept_name_nn NOT NULL, manager_id NUMBER(6), location_id NUMBER(4), CONSTRAINT dept_id_pk PRIMARY KEY(department_id) ); 注：对于一个PRIMARY KEY列UNIQUE索引被自动创建。

《Oracle Applications Developers Guide R11》是Oracle官方发布的开发文档，内容非常详细，涵盖了开发者所需的各项信息与指导。

Learning Hadoop.pdf #### This document, Learning Hadoop.pdf, provides a deep dive into Hadoop's core components and frameworks. Key sections cover Hadoop architecture, MapReduce processes, HDFS configurations, and best practices for managing big data with Hadoop. Each chapter offers insights into building reliable data ecosystems and efficiently handling large datasets, essential for mastering Hadoop operations.

数据查询语言（Data Query Language, DQL） SELECT SELECT * FROM table_name: 用于从指定表中选取所有列。 WHERE 子句：用于过滤结果集，只返回满足条件的记录。 示例： SELECT * FROM stock_information WHERE stockid = 'nid' AND stockname = 'str_name' 使用 LIKE 进行模糊匹配：stockname LIKE '%findthis%' 表示匹配包含“findthis”的字符串。 特殊的 LIKE 表达式：stockname LIKE '[a-zA-Z]%' 表示以字母开头的字符串；stockname LIKE '^[^F-M]%' 表示排除 F 到 M 之间的字母开头的字符串。 使用 OR 和 AND 组合多个条件：OR stockpath = 'stock_path' AND stockindex = 24 使用 NOT 关键字：NOT stocknumber = 10 使用 BETWEEN 指定一个范围：stocknumber BETWEEN 20 AND 100 使用 IN 指定一个值列表：stocknumber IN (10, 20, 30) 排序：ORDER BY stockid DESC 表示按降序排列；ORDER BY 1, 2 表示按第一列和第二列排序。 子查询：stockname = (SELECT stockname FROM stock_information WHERE stockid = 4) 表示内层查询的结果作为外层查询的条件。 DISTINCT SELECT DISTINCT column_name FROM table_name 用于返回唯一不重复的值。

Oracle 11g provides a wide array of built-in functions for database manipulation. This guide covers the most commonly used Oracle 11g functions, with detailed usage and examples to enhance your database operations. Functions such as TO_DATE, NVL, and SYSDATE are essential for efficient data retrieval and transformation. The document also explores aggregate functions, date functions, and numeric functions that are integral to Oracle 11g performance tuning and query optimization. This is your go-to reference for mastering Oracle 11g functions and leveraging them in your development projects.

The Oracle 10g documentation provides an in-depth exploration of the system, offering extensive resources and detailed instructions. This documentation is highly comprehensive, covering Oracle 10g architecture, installation, configuration, performance tuning, and troubleshooting. With its complete and thorough insights, this guide is essential for anyone working with Oracle 10g who seeks to maximize efficiency and understanding.